November 1998 arXiv papers — page 13

A. Ansari

Within the framework of selfconsistent cranked Hartree-Fock- Bogoliubov theory(one-dimensional) we predict second backbend in the yrast line of Os-182 at $I \approx 40 $, which is even sharper than the first one observed experimentally at $I \approx 14 $. Around such a high spin the structure becomes multi-quasiparticle type, but the main source of this stro

P. Danielewicz, D. A. Brown

We discuss imaging sources from low relative-velocity correlations in heavy-ion reactions. When the correlation is dominated by interference, we can obtain the images by Fourier transforming the correlation function. In the general case, we may use the method of optimized discretization. This method stabilizes the inversion by adapting the resolution of the

H. -W. Hammer

We discuss renormalization of the non-relativistic three-body problem with short-range forces. The problem becomes non-perturbative at momenta of the order of the inverse of the two-body scattering length, and an infinite number of graphs must be summed. This summation leads to a cutoff dependence that does not appear in any order in perturbation theory. We

P. F. Bedaque, H. -W. Hammer, U. van Kolck

We discuss renormalization of the non-relativistic three-body problem with short-range forces. The problem is non-perturbative at momenta of the order of the inverse of the two-body scattering length. An infinite number of graphs must be summed, which leads to a cutoff dependence that does not appear in any order in perturbation theory. We argue that this cu

E. N. Bukina, V. M. Dubovik

We discuss gauge freedom within the scope of the enlarged Helmholtz theorem and Neumann-Debye decomposition and then demonstrate its realization for the multipole expansion of a electromagnetic current with distinguished toroid moment family. The exact solution to the latter problem was obtained in 1974, but answers to some purely mathematical questions rais

Francisco J. Herranz, Mariano Santander

The family of quaternionic quasi-unitary (or quaternionic unitary Cayley--Klein algebras) is described in a unified setting. This family includes the simple algebras sp(N+1) and sp(p,q) in the Cartan series C_{N+1}, as well as many non-semisimple real Lie algebras which can be obtained from these simple algebras by particular contractions. The algebras in th

A. R. Its, N. A. Slavnov

We consider the local field dynamical temperature correlation function of the Quantum Nonlinear Schrodinger equation with the finite coupling constant. This correlation function admits a Fredholm determinant representation. The related operator-valued Riemann--Hilbert problem is used for analysing the leading term of the large time and long distance asymptot

Miriam Abdon, Fernando Torres

The genus g of an F_{q^2}-maximal curve satisfies g=g_1:=q(q-1)/2 or g\le g_2:= [(q-1)^2/4]. Previously, such curves with g=g_1 or g=g_2, q odd, have been characterized up to isomorphism. Here it is shown that an F_{q^2}-maximal curve with genus g_2, q even, is F_{q^2}-isomorphic to the nonsingular model of the plane curve \sum_{i=1}^{t}y^{q/2^i}=x^{q+1}, q=

J. Maurice Rojas

We consider the average-case complexity of some otherwise undecidable or open Diophantine problems. More precisely, we show that the following two problems can be solved in the complexity class PSPACE: (I) Given polynomials f_1,...,f_m in Z[x_1,...,x_n] defining a variety of dimension <=0 in C^n, find all solutions in Z^n of f_1=...=f_m=0. (II) For a given p

Jozef H. Przytycki, Adam S. Sikora

We give a short proof for a formula for the number of divisions of a convex (sn+2)-gon along non-crossing diagonals into (sj+2)-gons, where 1<=j<=n-1. In other words, we consider dissections of an (sn+2)-gon into pieces which can be further subdivided into (s+2)-gons. This formula generalizes the formulas for classical numbers of polygon dissections: Euler-C

J. F. Feinstein

In a previous note the author gave an example of a strong Ditkin algebra which does not have bounded relative units in the sense of Dales. In this note we investigate a certain family of Banach function algebras on the one point compactification of the natural numbers, and see that within this family are many easier examples of strong Ditkin algebras without

Tonnis A. ter Veldhuis

We analyze the structure of the moduli space of a supersymmetric SU(5) chiral gauge theory with two matter fields in the 10 representation, and two fields in the \bar{5} representation. Inspection of the exact Kahler potential of the classical moduli space shows that the symmetry group of the moduli space is larger than the global symmetry group of the under

Rajesh Gopakumar, Cumrun Vafa

The &#39;t Hooft expansion of SU(N) Chern-Simons theory on $S^3$ is proposed to be exactly dual to the topological closed string theory on the $S^2$ blow up of the conifold geometry. The $B$-field on the $S^2$ has magnitude $Ng_s=λ$, the &#39;t Hooft coupling. We are able to make a number of checks, such as finding exact agreement at the level of the partiti

Giovanni Amelino-Camelia, Jean-Pierre Derendinger

A relation between Wilson action and the Cornwall-Jackiw-Tomboulis effective action, which was recently suggested by Periwal, is here derived using path-integral techniques.

G. von Gehlen

In the solution of the superintegrable chiral Potts model special polynomials related to the representation theory of the Onsager algebra play a central role. We derive approximate analytic formulae for the zeros of particular polynomials which determine sets of low-lying energy eigenvalues of the chiral Potts quantum chain. These formulae allow the analytic

S. Forte, J. I. Latorre

We discuss the relation between the $c$--theorem and the the way various symmetries are realized in quantum field theory. We review our recent proof of the $c$--theorem in four dimensions. Based on this proof and further evidence, we conjecture that the realization of chiral symmetry be irreversible, flowing from the Wigner-Weyl realization at short distance

J. M. Aroca, Yu. A. Kubyshin

The derivation of the explicit formula for the vacuum expectation value of the Wilson loop functional for an arbitrary gauge group on an arbitrary orientable two-dimensional manifold is considered both in the continuum case and on the lattice. A contribution to this quantity, coming from the space of invariant connections, is also analyzed and is shown to be

L. Clavelli, P. H. Frampton

We discuss a model for neutrino masses and mixings based on R parity violating Yukawa couplings. The model requires no right-handed neutrinos. It accommodates the SuperKamiokande data on atmospheric neutrinos and successfully relates this data to the mass difference for solar neutrinos in the small-angle MSW solution. We obtain an unexpected testable pattern

James D. Wells, Alexander Moiseev, Jonathan F. Ormes

Interstellar antiproton fluxes can arise from dark matter annihilating or decaying into quarks or gluons that subsequently fragment into antiprotons. Evaporation of primordial black holes also can produce a significant antiproton cosmic-ray flux. Since the background of secondary antiprotons from spallation has an interstellar energy spectrum that peaks at $

Richard Wigmans

It is shown that high energy features of the cosmic ray spectrum, in particular the kink around 4 PeV and the corresponding change in spectral index, may be explained from interactions between highly energetic protons and relic Big Bang antineutrinos, if the latter have a rest mass of about 0.4 eV/$c^2$. This explanation is supported by experimental data fro

Shmuel Nussinov, Robert Shrock

We comment on some implications of theories with large compactification radii and TeV-scale quantum gravity. These include the behavior of high-energy gravitational scattering cross sections and consequences for ultra-high-energy cosmic rays and neutrino scattering, the question of how to generate naturally light neutrino masses, the issue of quark-lepton un

R. Jackiw

Recently proposed Lorentz-PCT noninvariant modifications of electromagnetism are reviewed. Their experimental consequences are described, and it is argued that available data decisively rules out their occurrence in Nature.

A. Yu. Ignatiev, G. C. Joshi, Kameshwar C. Wali

We examine the issue of magnetic charge quantization in the presence of black holes. It is pointed out that quantization of magnetic charge can lead to the mass quantization for magnetically charged black holes. We also discuss some implications for the experimental searches of magnetically charged black holes.

Guey-Lin Lin, Tzuu-Kang Chyi

We compute the Vilkovisky-DeWitt effective potential of a simplified version of the Standard Electroweak Model, where all charged boson fields as well as the bottom-quark field are neglected. The effective potential obtained in this formalism is gauge-independent. We derive from the effective potential the mass bound of the Higgs boson. The result is compare

A. F. Krutov, V. E. Troitsky

The charge form factor of the pion is calculated for momentum transfer range of Jefferson Lab experiments. The approach is based on the instant form of the relativistic Hamiltonian dynamics. It is shown that the form-factor dependence on the choice of the model for quark wave function in pion is weak, while the dependence on the constituent--quark mass is ra

Nico Schoonderwoerd

My thesis contains an introduction to Light-front Hamiltonian field theory and updates of published articles: - &#34;Equivalence of Covariant and Light-Front Perturbation Theory&#34; (hep-ph/9702311 and hep-ph/9806365, N. C. J. Schoonderwoerd and B. L. G. Bakker, published in Phys.Rev.D) and - &#34;Entanglement of Fock-space expansion and covariance in light

A. Hoecker

This talk summarizes the recent development in the evaluation of the leading order hadronic contributions to the running of the QED fine structure constant α(s), at $s=M_{\rm Z}^2$, and to the anomalous magnetic moments of the muon $(g-2)_μ$. The accuracy of the theoretical prediction of these observables is limited by the uncertainties on the hadronic contr

M. Göckeler, H. Hehl, P. E. L. Rakow, A. Schäfer

We have calculated complete spectra of the staggered Dirac operator on the lattice in quenched SU(3) gauge theory for β= 5.4 and various lattice sizes. The microscopic spectral density, the distribution of the smallest eigenvalue, and the two-point spectral correlation function are analyzed. We find the expected agreement of the lattice data with universal p

M. D&#39;Elia, A. Di Giacomo, E. Meggiolaro

We study, by numerical simulations on a lattice, the behaviour of the gauge-invariant nonlocal quark condensates in the QCD vacuum both in the quenched approximation and with four flavours of dynamical staggered fermions. The correlation length of the condensate is determined to be roughly twice as big as in the case of the gluon field strength correlators.

L. C. Garcia de Andrade

The dynamics of a gravitational torsion kink as a plane symmetric thick domain wall solution of Einstein-Cartan (EC) field equation is given. The spin-torsion energy has to be as high as the gravitational kink potential otherwise torsion will not contribute as an appreciable effect to domain wall.Cartan torsion also contributes to the orthonal pressure of th

Krzysztof R. Apt

We show that several constraint propagation algorithms (also called (local) consistency, consistency enforcing, Waltz, filtering or narrowing algorithms) are instances of algorithms that deal with chaotic iteration. To this end we propose a simple abstract framework that allows us to classify and compare these algorithms and to establish in a uniform way the

M. L. Nguyen, S. N. Coppersmith

We attempt to describe the stress distributions of granular packings using lattice-based layer-by-layer stochastic models that satisfy the constraints of force and torque balance and non-tensile forces at each site. The inherent asymmetry in the layer-by-layer approach appears to lead to an asymmetric force distribution, in disagreement with both experiments

Enzo Granato, S. C. Ying

The nonlinear response of an adsorbed layer on a periodic substrate to an external force is studied via a two dimensional uniaxial Frenkel-Kontorova model. The nonequlibrium properties of the model are simulated by Brownian molecular dynamics. Dynamical phase transitions between pinned solid, sliding commensurate and incommensurate solids and hysteresis effe

N. I. Lundin, L. Y. Gorelik, R. I. Shekhter, V. S. Shumeiko

We show that irradiation of a voltage-biased superconducting quantum point contact at frequencies of the order of the gap energy can remove the suppression of subgap dc transport through Andreev levels. Quantum interference among resonant scattering events involving photon absorption is furthermore shown to make microwave spectroscopy of the Andreev levels f

Kirill N Ilinski

In this paper we state the fundamental principles of the gauge approach to financial economics and demonstrate the ways of its application. In particular, modelling of realistic price processes is considered for an example of S&P500 market index. Derivative pricing and portfolio theory are also briefly discussed.

Iaroslav Ispolatov

Persistence in coarsening 1D spin systems with a power law interaction $r^{-1-σ}$ is considered. Numerical studies indicate that for sufficiently large values of the interaction exponent $σ$ ($σ\geq 1/2$ in our simulations), persistence decays as an algebraic function of the length scale $L$, $P(L)\sim L^{-θ}$. The Persistence exponent $θ$ is found to be ind

G. Johansson, K. N. Bratus&#39;, V. S. Shumeiko, G. Wendin

We present an approach for analyzing the dc current in voltage biased quantum superconducting junctions. By separating terms from different $n$-particle processes, we find that the $n$-particle current can be mapped on the problem of wave transport through a potential structure with $n$ barriers. We discuss the relation between resonances in such structures

Hermann Grabert, Gert-Ludwig Ingold

In the classical Josephson effect the phase difference across the junction is well defined, and the supercurrent is reduced only weakly by phase diffusion. For mesoscopic junctions with small capacitance the phase undergoes large quantum fluctuations, and the current is also decreased by Coulomb blockade effects. We discuss the behavior of the current-voltag

Matthias Vojta

The motion of a single hole in a 2D triangular antiferromagnet is investigated using the t-J model. The one-hole states are described by strings of spin deviations around the hole. Using projection technique the one-hole spectral function is calculated. For large J/t we find low-lying quasiparticle-like bands which are well separated from an incoherent backg

R. Heeb, D. F. Agterberg

Based on a two dimensional odd-parity superconducting order parameter for Sr_2RuO_4 with p-wave symmetry, we investigate the single vortex and vortex lattice structure of the mixed phase near H_{c1}. Ginzburg-Landau calculations for a single vortex show a fourfold structure with an orientation depending on the microscopic Fermi surface properties. The corres

T. Fujii, Y. Tsukamoto, N. Kawakami

Critical properties in photoemission spectra for the one-dimensional Mott insulator with orbital degeneracy are studied by exploiting the integrable {\it t-J} model, which is a supersymmetric generalization of the SU($n$) degenerate spin model. We discuss the critical properties for the holon dispersion as well as the spinon dispersions, by applying the conf

M. Nideroest, R. Frassanito, M. Saalfrank, A. C. Mota

The penetration field H_p of Bi_2Sr_2CaCu_2O_{8+delta} crystals is determined from magnetization curves for different field sweep rates dH/dt and temperatures. The obtained results are consistent with theoretical reports in the literature about vortex creep over surface and geometrical barriers. The frequently observed low-temperature upturn of H_p is shown

Dmitrii S. Golubev, Andrei D. Zaikin

We reply to the critique of our results raised by Aleiner, Altshuler and Gershenzon (AAG) in cond-mat/9808078 and cond-mat/9808053. We demonstrate that our path integral analysis fully reproduces the results of AAG if analyzed on a perturbative level. This should settle the issue of &#34;missing diagrams&#34; in our calculation. We, furthermore, demonstrate

Y. Bruynseraede, V. V. Moshchalkov

We report on flux confinement effects in superconducting submicron line, loop and dot structures. The main idea of our study was to vary the boundary conditions for confinement of the superconducting condensate by taking samples of different topology and, through that, modifying the lowest Landau level E_{LLL}(H). Since the critical temperature versus applie

A. Bergara, J. M. Pitarke, P. M. Echenique

The electronic response of a two-dimensional (2D) electron system represents a key quantity in discussing one-electron properties of electrons in semiconductor heterojunctions, on the surface of liquid helium and in copper-oxide planes of high-temperature superconductors. We here report an evaluation of the wave-vector and frequency dependent dynamical quadr

G. Hackenbroich, B. Rosenow, H. A. Weidenmueller

Motivated by a recent experiment by Buks et al. [Nature 391, 871 (1998)] we consider electron transport through an Aharonov-Bohm interferometer with a quantum dot in one of its arms. The quantum dot is coupled to a quantum system with a finite number of states acting as a which-path detector. The Aharonov-Bohm interference is calculated using a two-particle

Arne Brataas, Yu. V. Nazarov, J. Inoue, Gerrit E. W. Bauer

The non-equilibrium spin accumulation in ferromagnetic double barrier junctions is shown to govern the transport in small structures. Transport properties of such systems are described by a generalization of the theory of the Coulomb blockade. The spin accumulation enhances the magnetoresistance. The transient non-linear transport properties are predicted to

J. Auer, E. Krotscheck

We describe a rapidly converging algorithm for solving the Kohn--Sham equations and equations of similar structure that appear frequently in calculations of the structure of inhomogeneous electronic many--body systems. The algorithm has its roots the Hohenberg-Kohn theorem and solves directly for the electron density; single--particle wave functions are only

Krzysztof Sacha, Jakub Zakrzewski

The dynamics of Rydberg states of atomic hydrogen driven by elliptically polarized microwaves of frequency fulfilling 2:1 classical resonance condition is investigated both semiclassically and quantum mechanically in a simplified two-dimensional model of an atom. Semiclassical results for quasienergies of the system are shown to be in a good agreement with e

B. C. Bag, S. Chaudhuri, J. Ray Chaudhuri, D. S. Ray

We consider the quantum evolution of classically chaotic systems in contact with surroundings. Based on $\hbar$-scaling of an equation for time evolution of the Wigner&#39;s quasi-probability distribution function in presence of dissipation and thermal diffusion we derive a semiclassical equation for quantum fluctuations. This identifies an early regime of e

Pedro N. Safier

Recent estimates of magnetic field strengths in T Tauri stars yield values $B=1$--$4\,{\rm kG}$. In this paper, I present an upper limit to the photospheric values of $B$ by computing the equipartition values for different surface gravities and effective temperatures. The values of $B$ derived from the observations exceed this limit, and I examine the possib

Frank C. van den Bosch, Geraint F. Lewis, George Lake, Joachim Stadel

We examine the distributions of eccentricities of orbits within mass distributions like those we see for galaxies and clusters. A comprehensive understanding of these orbital properties is essential to calculate the rates of physical processes relevant to the formation and evolution of galaxies and clusters. We derive the orbital eccentricity distributions f

Edwin A. Bergin, David A. Neufeld, Gary J. Melnick

We have used a coupled dynamical and chemical model to examine the chemical changes induced by the passage of an interstellar shock in well shielded regions. Using this model we demonstrate that the formation of water in a shock will be followed in the post--shock phase by depletion of the water molecules onto the grain surfaces. To attempt to discriminate b

Ralph Engel

Experimental results obtained with the HERA collider and recent progress in their theoretical interpretation are reviewed. After a short introduction to HERA physics, deep inelastic scattering and photoproduction are discussed as (virtual) photon-proton scattering. It is shown that the measurement and theoretical understanding of both photoproduction as well

Dario Fadda, David Elbaz

Ten galaxy clusters, with redshift ranging from 0.2 to 1, have been observed with the ISO camera in the two bands LW2 and LW3 (centered respectively at 6.75 and 15 microns). We present a first analysis for three of these clusters at redshift 0.2, 0.5 and 1.

C. Murali

We study how massive halos respond to perturbations. Through numerical solution of the coupled linearized Boltzmann-Poisson equations, we find that halos transmit and amplify disturbances over large distances within galaxies. In particular, as Weinberg has noted, the halo provides an excellent medium for transmitting disturbances from the outer regions of ga

Marek Gierlinski, Andrzej A. Zdziarski

We analyze the simultaneous ASCA/RXTE observation of Cyg X-1 in the soft state on 1996 May 30. We apply a multi-color disk model with a torque-free boundary condition in the pseudo-Newtonian potential, and point out the main discrepancies between the commonly-used simplified `diskbb&#39; model and our one. We estimate the black hole mass and the accretion ra

D. J. Thompson

The telescopes on the Compton Gamma Ray Observatory (CGRO) have observed PSR B1055-52 a number of times between 1991 and 1998. From these data, a more detailed picture of the gamma radiation from this source has been developed, showing several characteristics which distinguish this pulsar: the light curve is complex; there is no detectable unpulsed emission;

E. F. Bell, R. G. Bower, R. S. de Jong, M. Hereld

Near-infrared (NIR) K&#39; images of a sample of five low surface brightness disc galaxies (LSBGs) were combined with optical data, with the aim of constraining their star formation histories. Both red and blue LSBGs were imaged to enable comparison of their stellar populations. For both types of galaxy strong colour gradients were found, consistent with mea

Y. N. Efremov, B. G. Elmegreen

Spontaneous and triggered star formation in the LMC is discussed with data on star clusters ages and positions. The supershell LMC4 and the stellar arcs in the same region are suggested to be triggered by GRBs, the progenitors of which might have escaped the old elliptical cluster NGC1978, close to which are a number of X-ray binaries and the SGR/SNR N49.

Tetsuya Shiromizu, Ryoichi Nishi

We take account of the lowest order back reaction on the fluid and modify the Kulsrud and Anderson equation $\partial_t{\cal E}_M= 2 γ{\cal E}_M$ obtained in the kinetic dynamo theory, where ${\cal E}_M$ is the energy density of the magnetic field. Furthermore, we apply our present result to some astrophysical stages where the magnetic field is expected to b

Geoffrey C. Bower, Heino Falcke, Don Backer, Melvyn Wright

We summarize the results of 7 mm VLBA imaging of Sgr A* and discuss some of the difficulties of accurately constraining the size of Sgr A* with VLBI observations. Our imaging results are fully consistent with the hypothesis that the VLBA image of Sgr A* is a resolved elliptical Gaussian caused by the scattering of an intervening thermal plasma. We show that

A. W. Strong, H. Bloemen, R. Diehl, W. Hermsen

Large-scale skymapping with COMPTEL using the full survey database presents challenging problems on account of the complex response and time-variable background. A new approach which attempts to address some of these problems is described, in which the information about each observation is preserved throughout the analysis. In this method, a maximum-entropy

L. Testi, F. Palla, A. Natta

The large body of near infrared observations presented in Testi et al. (1997; 1998) are analysed with the aim of characterizing the young stellar clusters surrounding Herbig Ae/Be stars. The results confirm the tendency of early Be stars to be surrounded by dense clusters of lower mass &#34;companions&#34;, while Ae stars are never found to be associated wit

Mark Walker, Mark Wardle

We present the germ of a new model for High Velocity Clouds, derived from the idea that the dark matter halo of our Galaxy is in the form of cold, planetary-mass gas clouds. In this picture HVCs arise as a result of disruptive collisions between dark matter clouds: high velocity atomic gas is a natural consequence of the dark halo kinematics, and is intimate

M. Asplund, D. L. Lambert, T. Kipper, D. Pollacco

The extraordinarily rapid evolution of the born-again giant Sakurai&#39;s object can be traced both in a continued cooling of the stellar surface and dramatic changes in chemical composition on a timescale of a mere few months. The abundance alterations are the results of the mixing and nuclear reactions which have ensued due to the final He-shell flash whic

G. Arutyunov, S. Frolov

The quadratic action for physical fields of type IIB supergravity model on $AdS_5\times S^5$ is derived starting from the recently found covariant action. All boundary terms that have to be added to the action to be used in the AdS/CFT correspondence are determined.

S. Karataglidis, P. J. Dortmans, K. Amos, C. Bennhold

Data for the scattering of 6He, 8He, 9Li, and 11Li from hydrogen are analyzed within a fully microscopic folding model of proton-nucleus scattering. Current data suggest that of these only 11Li has a noticeable halo. For 6He, we have also analysed the complementary reaction 6Li(gamma,pi)6He(gs). The available data for that reaction support the hypothesis tha

George B. Field, Sean M. Carroll

Primordial magnetic fields may account for all or part of the fields observed in galaxies. We consider the evolution of the magnetic fields created by pseudoscalar effects in the early universe. Such processes can create force-free fields of maximal helicity; we show that for such a field magnetic energy inverse cascades to larger scales than it would have s

Per Kraus, Finn Larsen, Sandip P. Trivedi

At zero temperature the Coulomb Branch of ${\cal N}=4$ super Yang-Mills theory is described in supergravity by multi-center solutions with D3-brane charge. At finite temperature and chemical potential the vacuum degeneracy is lifted, and minima of the free energy are shown to have a supergravity description as rotating black D3-branes. In the extreme limit t

Takayuki Hirayama, Koichi Yoshioka

In this paper we investigate N=1 supersymmetric gauge theories with a product gauge group. By using smoothly confining dynamics, we can find new dualities which include higher-rank tensor fields, and in which the dual gauge group is simple, not a product. Some of them are dualities between chiral and non-chiral gauge theories. We also discuss some applicatio

Hanno Hammer

Entanglement measures based on a logarithmic functional form naturally emerge in any attempt to quantify the degree of entanglement in the state of a multipartite quantum system. These measures can be regarded as generalizations of the classical Shannon-Wiener information of a probability distribution into the quantum regime. In the present work we introduce

Barbara Drossel

A simple model for the formation of a complex organism is introduced. Individuals can communicate and specialize, leading to an increase in productivity. If there are limits to the capacity of individuals to communicate with other individuals, the individuals form groups that interact with each other, leading to a complex organism that has interacting units

Luis E Mendes, Andrew R Liddle

The epoch when the Universe had a temperature higher than a GeV is long before any time at which we have reliable observations constraining the cosmological evolution. For example, the occurrence of a second burst of inflation (sometimes called thermal inflation) at a lower energy scale than standard inflation, or a short epoch of early matter domination, ca

Masahide Yamaguchi, M. Kawasaki, Jun&#39;ichi Yokoyama

Cosmological evolution of axionic strings is investigated by numerically solving field equations of a complex scalar field in 3+1 dimensions. It is shown that the global strings relax to the scaling solution with a significantly smaller number density than the case of local strings. The power spectrum of axions radiated from them is calculated from the simul

Asmita Mukherjee, Somdatta Bhattacharya

We investigate the issue of electromagnetic duality on the light front. We work with Zwanziger&#39;s theory of electric and magnetic sources which is appropriate for treating duality. When quantized on the light-front in the light front gauge, this theory yields two independent phase space degrees of freedom, namely the two transverse field components, the r

Yoshiharu Kawamura

We study the magnitudes of soft masses in heterotic string models with anomalous U(1) symmetry model-independently. In most cases, D-term contribution to soft scalar masses is expected to be comparable to or dominant over other contributions provided that supersymmetry breaking is mediated by the gravitational interaction and/or an anomalous U(1) symmetry an

C. Witte, M. Trucks

In this letter we discuss a new entanglement measure. It is based on the Hilbert-Schmidt norm of operators. We give an explicit formula for calculating the entanglement of a large set of states on C^2 \times C^2. Furthermore we find some relations between the entanglement of relative entropy and the Hilbert-Schmidt entanglement. A rigorous definition of part

Juan Pablo Paz, Wojciech Hubert Zurek

We investigate decoherence in the limit where the interaction with the environment is weak and the evolution is dominated by the self Hamiltonian of the system. We show that in this case quantized eigenstates of energy emerge as pointer states selected through the predictability sieve.

Jens Bolte, Stefan Keppeler

We derive a semiclassical time evolution kernel and a trace formula for the Dirac equation. The classical trajectories that enter the expressions are determined by the dynamics of relativistic point particles. We carefully investigate the transport of the spin degrees of freedom along the trajectories which can be understood geometrically as parallel transpo

G. Parzen

Symplectic tracking of beam particles using point magnets is achieved using a reference orbit made of circular arcs and straight lines that join smoothly with each other. For this choice of the reference orbit, results are given for the transfer functions, transfer matrices, and the transit times of the magnets and drift spaces. These results provide a sympl

J. Dobaczewski

We present a review of the mean-field approaches describing superdeformed states, which are currently used and/or being developed. As an example, we discuss in more details the properties of superdeformed A~60 nuclei, and present results of calculations for the rotational band in the doubly magic superdeformed nucleus 32S.

E. Babson, C. Chan

Several recent papers have addressed the problem of characterizing the $f$-vectors of cubical polytopes. This is largely motivated by the complete characterization of the $f$-vectors of simplicial polytopes given by Stanley, Billera, and Lee in 1980. Along these lines Blind and Blind have shown that unlike in the simplicial case, there are parity restriction

J. Scott Carter, Seiichi Kamada, Masahico Saito

A formula that relates triple points, branch points, and their distances from infinity is presented. We recover trivial normal Euler classes for oriented surfaces, and formulas on signed triple points.

Emilia Mezzetti, Dario Portelli

Let X be a scroll over a rational surface. We construct a linear system of surfaces in P^3 yielding a birational map from P^3 to X. We apply this construction to the scrolls of Bordiga and Palatini.

Daryl Cooper, Marc Lackenby

We show that, for any given 3-manifold M, there are at most finitely many hyperbolic knots K in the 3-sphere and fractions p/q (with q > 22), such that M is obtained by p/q surgery along K. This is a corollary of the following result. If M is obtained by Dehn filling the cusps of a hyperbolic 3-manifold X, where each filling slope has length more than 2 π+ ε

Dean Lee

Spherical field theory is a new non-perturbative method for studying quantum field theories. It uses the spherical partial wave expansion to reduce a general d-dimensional Euclidean field theory into a set of coupled one-dimensional systems. The coupled one-dimensional systems are then converted to partial differential equations and solved numerically. We de

Nick E. Mavromatos, Richard J. Szabo

A worldsheet approach to the study of non-abelian D-particle dynamics is presented based on viewing matrix-valued D-brane coordinate fields as coupling constants of a deformed sigma-model which defines a logarithmic conformal field theory. The short-distance structure of spacetime is shown to be naturally captured by the Zamolodchikov metric on the correspon

L. A. Manzoni, B. M. Pimentel, J. L. Tomazelli

In this work we consider the 2-point Green&#39;s functions in (1+1) dimensional quantum electrodynamics and show that the correct implementation of analytic regularization gives a gauge invariant result for the vaccum polarization amplitude and the correct coefficient for the axial anomaly.

L. Bégin, C. Cummins, P. Mathieu

This is the first of two articles devoted to a comprehensive exposition of the generating-function method for computing fusion rules in affine Lie algebras. The present paper is entirely devoted to the study of the tensor-product (infinite-level) limit of fusions rules. We consider thus in detail the problem of constructing tensor-product generating function

Pierre van Baal

We present the exact expression for the Nahm gauge field associated to a SU(N) charge one self-dual gauge field on T^3XR. The result implies that the size of the instanton is determined by the ``distance&#39;&#39; between its two flat connections at t plus or minus infinty.

M. Pawlowski, V. V. Papoyan, V. N. Pervushin, V. I. Smirichinski

The unification of general relativity and standard model for strong and electro-weak interactions is considered on the base of the conformal symmetry principle. The Penrose-Chernikov-Tagirov Lagrangian is used to describe the Higgs scalar field modulus and gravitation. We show that the procedure of the Hamiltonian reduction converts the homogeneous part of t

A. Nersessian

We analyze $S^1$ equivariant cohomology from the supergeometrical point of view. For this purpose we equip the external algebra of given manifold with equivariant even super(pre)symplectic structure, and show, that its Poincare-Cartan invariant defines equivariant Euler classes of surfaces. This allows to derive localization formulae by use of superanalog of

Ivan Andric, Velimir Bardek, Larisa Jonke

We consider a large-N Chern-Simons theory for the attractive bosonic matter (Jackiw-Pi model) in the Hamiltonian collective-field approach based on the 1/N expansion. We show that the dynamics of low-lying density excitations around the ground-state vortex configuration is equivalent to that of the Sutherland model. The relationship between the Chern-Simons

Jean-Loup Gervais, Mikhail Saveliev

It is shown that there exists an on-shell light cone gauge where half of the fermionic components of the super vector potential vanish, so that part of the superspace flatness conditions becomes linear. After reduction to $(1+1)$ space-time dimensions, the general solution of this subset of equations is derived. The remaining non-linear equations are written

M. Cvetic, H. Lu, C. N. Pope

We study the space-times of non-extremal intersecting p-brane configurations in M-theory, where one of the components in the intersection is a ``NUT,&#39;&#39; i.e. a configuration of the Taub-NUT type. Such a Taub-NUT configuration corresponds, upon compactification to D=4, to a Gross-Perry-Sorkin (GPS) monopole. We show that in the decoupling limit of the

Won Tae Kim, Chang-Yeong Lee, Dong Won Lee

We study the manifestly covariant three-dimensional symmetric Chern-Simons action in terms of the Batalin-Vilkovisky quantization method. We find that the Lorentz covariant gauge fixed version of this action is reduced to the usual Chern-Simons type action after a proper field redefinition. Furthermore, the renormalizability of the symmetric Chern-Simons the

P. Jizba, E. S. Tututi

We present a novel procedure for calculating non-equilibrium two-point Green&#39;s functions in the $O(N) ϕ^{4}$ theory at large $N$. The non-equilibrium density matrix $ρ$ is constructed via the Jaynes-Gibbs principle of maximal entropy and it is directly implemented into the Dyson-Schwinger equations through initial value conditions. In the large $N$ limit

Eli Cohen, L. P. Horwitz

We review the application of the Wigner-Weisskopf model for the neutral K meson system in the resolvent formalism. The Wigner-Weisskopf model is not equivalent to the Lee-Oehme-Yang-Wu formulation (which provides an accurate representation of the data). The residues in the pole approximation in the Wigner-Weisskopf model are not orthogonal, leading to additi

Hsin-Chia Cheng, Bogdan A. Dobrescu, Konstantin T. Matchev

We construct extensions of the Standard Model in which the gauge symmetries and supersymmetry prevent the dangerously large effects that may potentially be induced in a supersymmetric standard model by Planck scale physics. These include baryon number violation, flavor changing neutral currents, the $μ$ term, and masses for singlet or vector-like fields unde